Large computer, storage, or networking server systems, typically used in datacenters, require cooling. Often times liquid cooling systems are used to cool these systems. The liquid cooling system is typically a closed loop system that communicates chilled cooling fluid (coolant) to a cooling plate that is thermally coupled to a heat load (e.g., electronics) that requires cooling. The cooling plate transfers heat from the heat load to the coolant, and the heated coolant is communicated to a heat exchange for chilling.
Typically a rack or a chassis that is liquid cooled also includes multiple different airflow domains. An airflow domain, or more generally a gas flow domain, is a volume that is sealed from other gas flow domains and through which a gas (typically air) can be maintained at a positive pressure relative to ambient atmospheric pressure. There are liquid and air cooled equipment that require two or more gas flow domains that are independent and fluidly isolated from each other (e.g., fluidly sealed relative to each other). When a liquid coolant leak occurs in one of the domains, however, the coolant will tend to collect in the domain, as the domain is fluidly sealed from the other domains and from the external atmosphere.
To prevent pooling of coolant, some systems have unsealed airflow domains, typically through an unsealed drain outlet, to allow drainage from the airflow domain having liquid cooling components. This design, however, negatively impacts the air cooling effectiveness the airflow domains that are in communication with the unsealed drain outlet. Another design involves separate drainage paths for each domain. This design is more complex than the prior design, however, and is difficult to scale.